Robust Australopithecines

The members of the genusAustralopithecus--Australopithecines--are supposed by researchers to be the first common ancestor of apes and men, and they are the evolutionary step before the genus Homo.

The "robust" in robust Australopithecines refers not to the body, but to the jaws. Robust Australopithecines developed _gigantic_ teeth and jaws for the purposes of chomping down roots and fibers. To accomodate such gigantic jaws, they needed more muscle, so they evolved this thing called a sagittal crest to offer more surface area on the skull for muscle. They also had a fairly pronounced sexual dimorphism